Current laparoendoscopic practices require that the abdomen be filled with an inert gas such as carbon dioxide (insuffiated). This expands the abdominal cavity and allows the surgeon a working space between the patient's internal organs and the peritoneal wall. Once the cavity is expanded, surgical access is gained by puncturing the abdominal wall with a trocar and inserting a cannula. At the completion of the surgical procedure, it is considered desirable to close the puncture sites and thereby minimize the risk of wound infection, dehiscence and incisional hernia. This closure would classically be accomplished with a needle and suture.
In order to minimize the risk of injury to internal organs when a suture needle is inserted into the abdominal wall, the maintenance of abdominal expansion (pneumoperitoneum) is essential. Additionally, to ensure proper wound closure, the suture needle must be inserted at an angle which allows approximation of the innermost structures (i.e peritoneal wall and posterior fascia).
Several methods have been proposed for performing wound closure in laparoendoscopic procedures, among which there may be mentioned a device attributed to Grice. However, the prior art wound closure devices provide inadequate means of closing the trocar wound. In particular, the prior art devices have several problems. First, some devices do not provide a method to maintain insufflation of the abdominal cavity (pneumoperitoneum), as they require the removal of the cannula prior to the introduction of the suture instrument into the wound. This allows the insufflating gas to escape from the abdomen, thus partially or fully deflating the abdomen and further increasing the risk of perforating an internal organ.
Additionally, other devices do not provide any method for gauging the proper angle to capture the tissue to be proximated. The surgeon inserts the needle "free-hand" into the abdominal wall and must only assume that when the needle emerges through the fascia, it is in the correct angle.
Many of the prior art devices also require the use of additional instruments to complete the procedure. In other designs, once the needle is initially inserted through the abdominal wall, the control of the suture is transferred from the needle to a grasper. The grasper retains the suture until the needle can be removed and reinserted on the opposite side of the puncture wound. Using the grasper, the surgeon must then rethread the suture into the needle before the needle can be withdrawn, thus completing the suture loop. The entirety of this procedure must be done under direct vision. This requires that the surgeon devote both hands to the procedure, in addition to requiting an assistant to position the laparoscope and assist in attaching the suture to the needle on its second insertion.
Finally, some instruments require that the suture be threaded through the entire length of a hollow insertion needle, which makes use of such devices time consuming and difficult.
The present invention provides solutions to the various problems noted above with respect to the prior art wound closure devices, and methods of manufacturing such devices.